Molecular Detection of lsa21 Gene Encoding an Adhesion Protein Among Pathogenic Leptospiral Serovars

Background: Leptospirosis, as an emerging global public health problem, is a widespread zoonosis and substantial infectious disease caused by pathogenic Leptospira spp. The diagnosis of the disease remains a challenge due to its non-specific clinical symptoms. The Lsa21 protein is one of the leptospiral proteins that has extracellular matrix-binding properties that are expressed during the infection of pathogenic Leptospira serovars. Objectives: The study aimed to assess the presence of the lsa21 gene in Leptospira serovars. Materials and Methods: The study was conducted on 22 pathogenic Leptospira serovars and non-pathogenic Leptospira serovars, obtained from the Reference Laboratory for Leptospira, Razi Vaccine, and Serum Research Institute, Karaj, Iran. DNA Leptospira serovars were extracted and amplified by the polymerase chain reaction (PCR) using specific primers. Results: An approximately 540-bp DNA fragment from the DNA of all pathogenic Leptospira serovars was amplified by the PCR not found in non-pathogenic serovars. Conclusion: Molecular detection of pathogenic leptospires based on the lsa21 gene can be utilized for laboratory diagnosis and could be a good candidate for developing vaccines against leptospirosis.